src/map_masq.erl - erlang/mgw_nat - Gitiles

 % MAP masquerading application

 % (C) 2010-2011 by Harald Welte <laforge@gnumonks.org>
 % (C) 2010-2011 by On-Waves
 %
 % All Rights Reserved
 %
 % This program is free software; you can redistribute it and/or modify
 % it under the terms of the GNU General Public License as published by
 % the Free Software Foundation; either version 2 of the License, or
 % (at your option) any later version.
 %
 % This program is distributed in the hope that it will be useful,
 % but WITHOUT ANY WARRANTY; without even the implied warranty of
 % MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 % GNU General Public License for more details.
 %
 % You should have received a copy of the GNU General Public License along
 % with this program; if not, write to the Free Software Foundation, Inc.,
 % 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.


 -module(map_masq).
 -author('Harald Welte <laforge@gnumonks.org>').
 %-compile(export_all).

 -export([mangle_map/2]).

 -define(PATCH_HLR_NUMBER, [1]).
 -define(PATCH_SGSN_NUMBER, [2]).
 -define(PATCH_SGSN_ADDRESS, [3]).
 -define(PATCH_VMSC_ADDRESS, [4]).
 -define(PATCH_GSMSCF_ADDRESS, [5]).

 -include_lib("osmo_map/include/map.hrl").

 mangle_msisdn(from_stp, _Opcode, AddrIn) ->
 	{ok, IntPfx} = application:get_env(intern_pfx),
 	mgw_nat:isup_party_internationalize(AddrIn, IntPfx).

 % Someobdy inquires on Routing Info for a MS (from HLR)
 patch(#'SendRoutingInfoArg'{msisdn = Msisdn} = P) ->
 	AddrInDec = map_codec:parse_addr_string(Msisdn),
 	io:format("MSISDN IN = ~p~n", [AddrInDec]),
 	AddrOutDec = mangle_msisdn(from_stp, 22, AddrInDec),
 	io:format("MSISDN OUT = ~p~n", [AddrOutDec]),
 	AddrOutBin = map_codec:encode_addr_string(AddrOutDec),
 	P#'SendRoutingInfoArg'{msisdn = AddrOutBin};

 % HLR responds with Routing Info for a MS
 patch(#'SendRoutingInfoRes'{extendedRoutingInfo = ExtRoutInfo,
 			    'vmsc-Address' = VmscAddress} = P) ->
 	P#'SendRoutingInfoRes'{extendedRoutingInfo = patch(ExtRoutInfo),
 			       'vmsc-Address' = ?PATCH_VMSC_ADDRESS};
 patch(#'CamelRoutingInfo'{gmscCamelSubscriptionInfo = GmscCamelSI} = P) ->
 	P#'CamelRoutingInfo'{gmscCamelSubscriptionInfo = patch(GmscCamelSI)};
 patch({camelRoutingInfo, CRI}) ->
 	{camelRoutingInfo, patch(CRI)};
 patch({routingInfo, RI}) ->
 	{routingInfo, patch(RI)};

 % patch the roaming number as it is sent from HLR to G-MSC (SRI Resp)
 patch({roamingNumber, RoamNumTBCD}) ->
 	RoamNumIn = map_codec:parse_addr_string(RoamNumTBCD),
 	io:format("Roaming Number IN = ~p~n", [RoamNumIn]),
 	{ok, MsrnPfxStp} = application:get_env(msrn_pfx_stp),
 	{ok, MsrnPfxMsc} = application:get_env(msrn_pfx_msc),
 	RoamNumOut = mgw_nat:isup_party_replace_prefix(RoamNumIn, MsrnPfxMsc, MsrnPfxStp),
 	io:format("Roaming Number OUT = ~p~n", [RoamNumOut]),
 	RoamNumOutTBCD = map_codec:encode_addr_string(RoamNumOut),
 	{roamingNumber, RoamNumOutTBCD};


 % patch a UpdateGprsLocationArg and replace SGSN number and SGSN address
 % !!! TESTING ONLY !!!
 patch(#'UpdateGprsLocationArg'{} = P) ->
 	P#'UpdateGprsLocationArg'{'sgsn-Number'= ?PATCH_SGSN_NUMBER,
 				  'sgsn-Address' = ?PATCH_SGSN_ADDRESS};

 % Some other SGSN is sendingu us a GPRS location update.  In the response,
 % we indicate teh HLR number, which we need to masquerade
 patch(#'UpdateGprsLocationRes'{} = P) ->
 	P#'UpdateGprsLocationRes'{'hlr-Number' = ?PATCH_HLR_NUMBER};

 % Some other MSC/VLR is sendingu us a GSM location update.  In the response,
 % we indicate teh HLR number, which we need to masquerade
 patch(#'UpdateLocationRes'{} = P) ->
 	P#'UpdateLocationRes'{'hlr-Number' = ?PATCH_HLR_NUMBER};

 % HLR responds to VLR's MAP_RESTORE_REQ (i.e. it has lost information)
 patch(#'RestoreDataRes'{} = P) ->
 	P#'RestoreDataRes'{'hlr-Number' = ?PATCH_HLR_NUMBER};

 % HLR sends subscriber data to VLR/SGSN, including CAMEL info
 patch(#'InsertSubscriberDataArg'{'vlrCamelSubscriptionInfo'=VlrCamel,
 				 'sgsn-CAMEL-SubscriptionInfo'=SgsnCamel} = Arg) ->
 	Arg#'InsertSubscriberDataArg'{'vlrCamelSubscriptionInfo'=patch(VlrCamel),
 				      'sgsn-CAMEL-SubscriptionInfo'=patch(SgsnCamel)};

 % HLR sends subscriber data to gsmSCF
 patch(#'AnyTimeSubscriptionInterrogationRes'{'camel-SubscriptionInfo'=Csi} = P) ->
 	P#'AnyTimeSubscriptionInterrogationRes'{'camel-SubscriptionInfo'=patch(Csi)};

 patch(asn1_NOVALUE) ->
 	asn1_NOVALUE;

 % CAMEL related parsing

 % this is part of the SRI Response (HLR->GMSC)
 patch(#'GmscCamelSubscriptionInfo'{'o-CSI'=Ocsi, 't-CSI'=Tcsi,
 				   'd-csi'=Dcsi} = P) ->
 	P#'GmscCamelSubscriptionInfo'{'o-CSI'=patch(Ocsi),
 				      't-CSI'=patch(Tcsi),
 				      'd-csi'=patch(Dcsi)};

 % this is part of the InsertSubscriberData HLR -> VLR
 patch(#'VlrCamelSubscriptionInfo'{'o-CSI'=Ocsi, 'mo-sms-CSI'=MoSmsCsi,
 				  'mt-sms-CSI'=MtSmsCsi, 'ss-CSI'=SsCsi} = P) ->
 	P#'VlrCamelSubscriptionInfo'{'o-CSI'=patch(Ocsi),
 				    'mo-sms-CSI'=patch(MoSmsCsi),
 				    'mt-sms-CSI'=patch(MtSmsCsi),
 				    'ss-CSI'=patch(SsCsi)};

 % this is part of the InsertSubscriberData HLR -> SGSN
 patch(#'SGSN-CAMEL-SubscriptionInfo'{'gprs-CSI'=GprsCsi,
 				     'mo-sms-CSI'=MoSmsCsi,
 				     'mt-sms-CSI'=MtSmsCsi} = P) ->
 	P#'SGSN-CAMEL-SubscriptionInfo'{'gprs-CSI'=patch(GprsCsi),
 					'mo-sms-CSI'=patch(MoSmsCsi),
 					'mt-sms-CSI'=patch(MtSmsCsi)};

 % this is part of the Anytime Subscription Interrogation Result HLR->gsmSCF
 patch(#'CAMEL-SubscriptionInfo'{'o-CSI'=Ocsi,
 				'd-CSI'=Dcsi,
 				't-CSI'=Tcsi,
 				'vt-CSI'=Vtcsi,
 				%'tif-CSI'=Tifcsi,
 				'gprs-CSI'=GprsCsi,
 				'mo-sms-CSI'=MoSmsCsi,
 				'ss-CSI'=SsCsi,
 				'm-CSI'=Mcsi,
 				'mt-sms-CSI'=MtSmsCsi,
 				'mg-csi'=MgCsi,
 				'o-IM-CSI'=OimCsi,
 				'd-IM-CSI'=DimCsi,
 				'vt-IM-CSI'=VtImCsi} = P) ->
 	P#'CAMEL-SubscriptionInfo'{'o-CSI'=patch(Ocsi),
 				'd-CSI'=patch(Dcsi),
 				't-CSI'=patch(Tcsi),
 				'vt-CSI'=patch(Vtcsi),
 				'gprs-CSI'=patch(GprsCsi),
 				'mo-sms-CSI'=patch(MoSmsCsi),
 				'ss-CSI'=patch(SsCsi),
 				'm-CSI'=patch(Mcsi),
 				'mt-sms-CSI'=patch(MtSmsCsi),
 				'mg-csi'=patch(MgCsi),
 				'o-IM-CSI'=patch(OimCsi),
 				'd-IM-CSI'=patch(DimCsi),
 				'vt-IM-CSI'=patch(VtImCsi)};

 patch(#'T-CSI'{'t-BcsmCamelTDPDataList'=TdpList} = P) ->
 	P#'T-CSI'{'t-BcsmCamelTDPDataList'=patch_tBcsmCamelTDPDataList(TdpList)};
 patch(#'M-CSI'{'gsmSCF-Address'=GsmScfAddr} = P) ->
 	P#'M-CSI'{'gsmSCF-Address'=?PATCH_GSMSCF_ADDRESS};
 patch(#'MG-CSI'{'gsmSCF-Address'=GsmScfAddr} = P) ->
 	P#'MG-CSI'{'gsmSCF-Address'=?PATCH_GSMSCF_ADDRESS};
 patch(#'O-CSI'{'o-BcsmCamelTDPDataList'=TdpList} = P) ->
 	P#'O-CSI'{'o-BcsmCamelTDPDataList'=patch_oBcsmCamelTDPDataList(TdpList)};
 patch(#'D-CSI'{'dp-AnalysedInfoCriteriaList'=List} = P) ->
 	P#'D-CSI'{'dp-AnalysedInfoCriteriaList'=patch_AnInfoCritList(List)};
 patch(#'SMS-CSI'{'sms-CAMEL-TDP-DataList'=TdpList} = P) ->
 	P#'SMS-CSI'{'sms-CAMEL-TDP-DataList'=patch_SmsCamelTDPDataList(TdpList)};
 patch(#'SS-CSI'{'ss-CamelData'=Sscd} = P) ->
 	P#'SS-CSI'{'ss-CamelData'=patch(Sscd)};
 patch(#'GPRS-CSI'{'gprs-CamelTDPDataList'=TdpList} = P) ->
 	P#'GPRS-CSI'{'gprs-CamelTDPDataList'=patch_GprsCamelTDPDataList(TdpList)};
 patch(#'SS-CamelData'{'gsmSCF-Address'=GsmScfAddr} = P) ->
 	P#'SS-CamelData'{'gsmSCF-Address'=?PATCH_GSMSCF_ADDRESS};
 patch(#'O-BcsmCamelTDPData'{'gsmSCF-Address'=GsmScfAddr} = P) ->
 	P#'O-BcsmCamelTDPData'{'gsmSCF-Address'=?PATCH_GSMSCF_ADDRESS};
 patch(#'SMS-CAMEL-TDP-Data'{'gsmSCF-Address'=GsmScfAddr} = P) ->
 	P#'SMS-CAMEL-TDP-Data'{'gsmSCF-Address'=?PATCH_GSMSCF_ADDRESS};
 patch(#'GPRS-CamelTDPData'{'gsmSCF-Address'=GsmScfAddr} = P) ->
 	P#'GPRS-CamelTDPData'{'gsmSCF-Address'=?PATCH_GSMSCF_ADDRESS};
 patch(#'DP-AnalysedInfoCriterium'{'gsmSCF-Address'=GsmScfAddr} = P) ->
 	P#'DP-AnalysedInfoCriterium'{'gsmSCF-Address'=?PATCH_GSMSCF_ADDRESS};
 patch(Default) ->
 	Default.

 patch_oBcsmCamelTDPDataList(List) ->
 	% we reverse the origianl list, as the tail recursive _acc function
 	% will invert the order of components again
 	patch_oBcsmCamelTDPDataList_acc(lists:reverse(List), []).
 patch_oBcsmCamelTDPDataList_acc([], NewList) -> NewList;
 patch_oBcsmCamelTDPDataList_acc([TdpData|Tail], NewList) ->
 	NewTdpData = patch(TdpData#'O-BcsmCamelTDPData'{}),
 	patch_oBcsmCamelTDPDataList_acc(Tail, [NewTdpData|NewList]).

 patch_tBcsmCamelTDPDataList(List) ->
 	% we reverse the origianl list, as the tail recursive _acc function
 	% will invert the order of components again
 	patch_tBcsmCamelTDPDataList_acc(lists:reverse(List), []).
 patch_tBcsmCamelTDPDataList_acc([], NewList) -> NewList;
 patch_tBcsmCamelTDPDataList_acc([TdpData|Tail], NewList) ->
 	NewTdpData = patch(TdpData#'T-BcsmCamelTDPData'{}),
 	patch_tBcsmCamelTDPDataList_acc(Tail, [NewTdpData|NewList]).

 patch_AnInfoCritList(List) ->
 	% we reverse the origianl list, as the tail recursive _acc function
 	% will invert the order of components again
 	patch_AnInfoCritList_acc(lists:reverse(List), []).
 patch_AnInfoCritList_acc([], NewList) -> NewList;
 patch_AnInfoCritList_acc([Crit|Tail], NewList) ->
 	NewCrit = patch(Crit#'DP-AnalysedInfoCriterium'{}),
 	patch_AnInfoCritList_acc(Tail, [NewCrit|NewList]).

 patch_GprsCamelTDPDataList(List) ->
 	% we reverse the origianl list, as the tail recursive _acc function
 	% will invert the order of components again
 	patch_GprsCamelTDPDataList_acc(lists:reverse(List), []).
 patch_GprsCamelTDPDataList_acc([], NewList) -> NewList;
 patch_GprsCamelTDPDataList_acc([TdpData|Tail], NewList) ->
 	NewTdpData = patch(TdpData#'GPRS-CamelTDPData'{}),
 	patch_GprsCamelTDPDataList_acc(Tail, [NewTdpData|NewList]).

 patch_SmsCamelTDPDataList(List) ->
 	% we reverse the origianl list, as the tail recursive _acc function
 	% will invert the order of components again
 	patch_SmsCamelTDPDataList_acc(lists:reverse(List), []).
 patch_SmsCamelTDPDataList_acc([], NewList) -> NewList;
 patch_SmsCamelTDPDataList_acc([TdpData|Tail], NewList) ->
 	NewTdpData = patch(TdpData#'SMS-CAMEL-TDP-Data'{}),
 	patch_GprsCamelTDPDataList_acc(Tail, [NewTdpData|NewList]).


 % process the Argument of a particular MAP invocation
 process_component_arg(_From, OpCode, Arg) ->
 	case Arg of
 		asn1_NOVALUE -> Arg;
 		_ -> patch(Arg)
 	end.

 % recurse over all components
 handle_tcap_components(_From, asn1_NOVALUE) ->
 	asn1_NOVALUE;
 handle_tcap_components(From, List) ->
 	% we reverse the origianl list, as the tail recursive _acc function
 	% will invert the order of components again
 	handle_tcap_components_acc(From, lists:reverse(List), []).
 handle_tcap_components_acc(_From, [], NewComponents) -> NewComponents;
 handle_tcap_components_acc(From, [Component|Tail], NewComponents) ->
 	case Component of
 		{basicROS, {Primitive, Body}} ->
 			io:format("handle component ~p primitive ~n", [Component]),
 			case Body of
 				% BEGIN
 				#'MapSpecificPDUs_begin_components_SEQOF_basicROS_invoke'{opcode={local, OpCode},
 											  argument=Arg} ->
 					NewArg = process_component_arg(From, OpCode, Arg),
 					NewBody = Body#'MapSpecificPDUs_begin_components_SEQOF_basicROS_invoke'{argument=NewArg};
 				#'MapSpecificPDUs_begin_components_SEQOF_basicROS_returnResult'{result=#'MapSpecificPDUs_begin_components_SEQOF_basicROS_returnResult_result'{opcode={local, OpCode}, result=Arg} = R} ->
 					NewArg = process_component_arg(From, OpCode, Arg),
 					NewBody = Body#'MapSpecificPDUs_begin_components_SEQOF_basicROS_returnResult'{result=R#'MapSpecificPDUs_begin_components_SEQOF_basicROS_returnResult_result'{result=NewArg}};
 				#'MapSpecificPDUs_begin_components_SEQOF_returnResultNotLast'{result=#'MapSpecificPDUs_begin_components_SEQOF_returnResultNotLast_result'{opcode={local, OpCode}, result=Arg} = R} ->
 					NewArg = process_component_arg(From, OpCode, Arg),
 					NewBody = Body#'MapSpecificPDUs_begin_components_SEQOF_returnResultNotLast'{result=R#'MapSpecificPDUs_begin_components_SEQOF_returnResultNotLast_result'{result=NewArg}};
 				% END
 				#'MapSpecificPDUs_end_components_SEQOF_basicROS_invoke'{opcode={local, OpCode},
 											argument=Arg} ->
 					NewArg = process_component_arg(From, OpCode, Arg),
 					NewBody = Body#'MapSpecificPDUs_end_components_SEQOF_basicROS_invoke'{argument=NewArg};
 				#'MapSpecificPDUs_end_components_SEQOF_basicROS_returnResult'{result=#'MapSpecificPDUs_end_components_SEQOF_basicROS_returnResult_result'{opcode={local, OpCode}, result=Arg} = R} ->
 					NewArg = process_component_arg(From, OpCode, Arg),
 					NewBody = Body#'MapSpecificPDUs_end_components_SEQOF_basicROS_returnResult'{result=R#'MapSpecificPDUs_end_components_SEQOF_basicROS_returnResult_result'{result=NewArg}};
 				#'MapSpecificPDUs_end_components_SEQOF_returnResultNotLast'{result=#'MapSpecificPDUs_end_components_SEQOF_returnResultNotLast_result'{opcode={local, OpCode}, result=Arg} = R} ->
 					NewArg = process_component_arg(From, OpCode, Arg),
 					NewBody = Body#'MapSpecificPDUs_end_components_SEQOF_returnResultNotLast'{result=R#'MapSpecificPDUs_end_components_SEQOF_returnResultNotLast_result'{result=NewArg}};
 				% CONTINUE
 				#'MapSpecificPDUs_continue_components_SEQOF_basicROS_invoke'{opcode={local, OpCode},
 											     argument=Arg} ->
 					NewArg = process_component_arg(From, OpCode, Arg),
 					NewBody = Body#'MapSpecificPDUs_continue_components_SEQOF_basicROS_invoke'{argument=NewArg};
 				#'MapSpecificPDUs_continue_components_SEQOF_basicROS_returnResult'{result=#'MapSpecificPDUs_continue_components_SEQOF_basicROS_returnResult_result'{opcode={local, OpCode}, result=Arg} = R} ->
 					NewArg = process_component_arg(From, OpCode, Arg),
 					NewBody = Body#'MapSpecificPDUs_end_components_SEQOF_basicROS_returnResult'{result=R#'MapSpecificPDUs_end_components_SEQOF_basicROS_returnResult_result'{result=NewArg}};
 				#'MapSpecificPDUs_continue_components_SEQOF_returnResultNotLast'{result=#'MapSpecificPDUs_continue_components_SEQOF_returnResultNotLast_result'{opcode={local, OpCode}, result=Arg} = R} ->
 					NewArg = process_component_arg(From, OpCode, Arg),
 					NewBody = Body#'MapSpecificPDUs_continue_components_SEQOF_returnResultNotLast'{result=R#'MapSpecificPDUs_continue_components_SEQOF_returnResultNotLast_result'{result=NewArg}};
 				_ ->
 					NewBody = Body
 			end,
 			%NewBody = setelement(5, Body, NewArg)
 			NewComponent = {basicROS, {Primitive, NewBody}};
 		_ ->
 			NewComponent = Component
 	end,
 	io:format("=> modified component ~p~n", [NewComponent]),
 	handle_tcap_components_acc(From, Tail, [NewComponent|NewComponents]).


 % Erlang asn1rt has this strange property that all incoming EXTERNAL types are
 % converted from the 1990 version into the 1994 version.  The latter does not
 % preserve the encoding (octet string, single ASN1 type, ...).  During encoding,
 % it then uses the OCTTET-STRING encoding, which is different from the MAP
 % customary single-ASN1-type format.
 asn1_EXTERNAL1994_fixup({'EXTERNAL', DirRef, IndRef, Data}) when is_list(Data);is_binary(Data) ->
 	% our trick is as follows: we simply convert back to 1990 format, and explicitly
 	% set the single-ASN1-type encoding.  asn1rt:s 'enc_EXTERNAL'() will detect this
 	#'EXTERNAL'{'direct-reference' = DirRef, 'indirect-reference' = IndRef,
 		    'encoding' = {'single-ASN1-type', Data}};
 asn1_EXTERNAL1994_fixup(Foo) ->
 	Foo.


 handle_tcap_dialogue(_From, Foo = {'EXTERNAL', DirRef, IndRef, Data}) ->
 	asn1_EXTERNAL1994_fixup(Foo);
 handle_tcap_dialogue(_From, Foo) ->
 	Foo.


 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 % Actual mangling of the decoded MAP messages
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 mangle_map(From, {Type, TcapMsgDec}) ->
 	case {Type, TcapMsgDec} of
 	{'unidirectional', #'MapSpecificPDUs_unidirectional'{dialoguePortion=Dialg,
 							     components=Components}} ->
 		NewDialg = handle_tcap_dialogue(From, Dialg),
 		NewComponents = handle_tcap_components(From, Components),
 		NewTcapMsgDec = TcapMsgDec#'MapSpecificPDUs_unidirectional'{dialoguePortion=NewDialg, components=NewComponents};
 	{'begin', #'MapSpecificPDUs_begin'{dialoguePortion=Dialg, components=Components}} ->
 		NewDialg = handle_tcap_dialogue(From, Dialg),
 		NewComponents = handle_tcap_components(From, Components),
 		NewTcapMsgDec = TcapMsgDec#'MapSpecificPDUs_begin'{dialoguePortion=NewDialg, components=NewComponents};
 	{'continue', #'MapSpecificPDUs_continue'{dialoguePortion=Dialg, components=Components}} ->
 		NewDialg = handle_tcap_dialogue(From, Dialg),
 		NewComponents = handle_tcap_components(From, Components),
 		NewTcapMsgDec = TcapMsgDec#'MapSpecificPDUs_continue'{dialoguePortion=NewDialg, components=NewComponents};
 	{'end', #'MapSpecificPDUs_end'{dialoguePortion=Dialg, components=Components}} ->
 		NewDialg = handle_tcap_dialogue(From, Dialg),
 		NewComponents = handle_tcap_components(From, Components),
 		NewTcapMsgDec = TcapMsgDec#'MapSpecificPDUs_end'{dialoguePortion=NewDialg, components=NewComponents};
 	%{_, #'Abort'{reason=Reason} ->
 	_ ->
 		NewTcapMsgDec = TcapMsgDec
 	end,
 	io:format("new TcapMsgDec (Type=~p) ~p~n", [Type, NewTcapMsgDec]),
 	{Type, NewTcapMsgDec}.
	% MAP masquerading application

	% (C) 2010-2011 by Harald Welte <laforge@gnumonks.org>
	% (C) 2010-2011 by On-Waves
	%
	% All Rights Reserved
	%
	% This program is free software; you can redistribute it and/or modify
	% it under the terms of the GNU General Public License as published by
	% the Free Software Foundation; either version 2 of the License, or
	% (at your option) any later version.
	%
	% This program is distributed in the hope that it will be useful,
	% but WITHOUT ANY WARRANTY; without even the implied warranty of
	% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	% GNU General Public License for more details.
	%
	% You should have received a copy of the GNU General Public License along
	% with this program; if not, write to the Free Software Foundation, Inc.,
	% 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.


	-module(map_masq).
	-author('Harald Welte <laforge@gnumonks.org>').
	%-compile(export_all).

	-export([mangle_map/2]).

	-define(PATCH_HLR_NUMBER, [1]).
	-define(PATCH_SGSN_NUMBER, [2]).
	-define(PATCH_SGSN_ADDRESS, [3]).
	-define(PATCH_VMSC_ADDRESS, [4]).
	-define(PATCH_GSMSCF_ADDRESS, [5]).

	-include_lib("osmo_map/include/map.hrl").

	mangle_msisdn(from_stp, _Opcode, AddrIn) ->
	{ok, IntPfx} = application:get_env(intern_pfx),
	mgw_nat:isup_party_internationalize(AddrIn, IntPfx).

	% Someobdy inquires on Routing Info for a MS (from HLR)
	patch(#'SendRoutingInfoArg'{msisdn = Msisdn} = P) ->
	AddrInDec = map_codec:parse_addr_string(Msisdn),
	io:format("MSISDN IN = ~p~n", [AddrInDec]),
	AddrOutDec = mangle_msisdn(from_stp, 22, AddrInDec),
	io:format("MSISDN OUT = ~p~n", [AddrOutDec]),
	AddrOutBin = map_codec:encode_addr_string(AddrOutDec),
	P#'SendRoutingInfoArg'{msisdn = AddrOutBin};

	% HLR responds with Routing Info for a MS
	patch(#'SendRoutingInfoRes'{extendedRoutingInfo = ExtRoutInfo,
	'vmsc-Address' = VmscAddress} = P) ->
	P#'SendRoutingInfoRes'{extendedRoutingInfo = patch(ExtRoutInfo),
	'vmsc-Address' = ?PATCH_VMSC_ADDRESS};
	patch(#'CamelRoutingInfo'{gmscCamelSubscriptionInfo = GmscCamelSI} = P) ->
	P#'CamelRoutingInfo'{gmscCamelSubscriptionInfo = patch(GmscCamelSI)};
	patch({camelRoutingInfo, CRI}) ->
	{camelRoutingInfo, patch(CRI)};
	patch({routingInfo, RI}) ->
	{routingInfo, patch(RI)};

	% patch the roaming number as it is sent from HLR to G-MSC (SRI Resp)
	patch({roamingNumber, RoamNumTBCD}) ->
	RoamNumIn = map_codec:parse_addr_string(RoamNumTBCD),
	io:format("Roaming Number IN = ~p~n", [RoamNumIn]),
	{ok, MsrnPfxStp} = application:get_env(msrn_pfx_stp),
	{ok, MsrnPfxMsc} = application:get_env(msrn_pfx_msc),
	RoamNumOut = mgw_nat:isup_party_replace_prefix(RoamNumIn, MsrnPfxMsc, MsrnPfxStp),
	io:format("Roaming Number OUT = ~p~n", [RoamNumOut]),
	RoamNumOutTBCD = map_codec:encode_addr_string(RoamNumOut),
	{roamingNumber, RoamNumOutTBCD};


	% patch a UpdateGprsLocationArg and replace SGSN number and SGSN address
	% !!! TESTING ONLY !!!
	patch(#'UpdateGprsLocationArg'{} = P) ->
	P#'UpdateGprsLocationArg'{'sgsn-Number'= ?PATCH_SGSN_NUMBER,
	'sgsn-Address' = ?PATCH_SGSN_ADDRESS};

	% Some other SGSN is sendingu us a GPRS location update. In the response,
	% we indicate teh HLR number, which we need to masquerade
	patch(#'UpdateGprsLocationRes'{} = P) ->
	P#'UpdateGprsLocationRes'{'hlr-Number' = ?PATCH_HLR_NUMBER};

	% Some other MSC/VLR is sendingu us a GSM location update. In the response,
	% we indicate teh HLR number, which we need to masquerade
	patch(#'UpdateLocationRes'{} = P) ->
	P#'UpdateLocationRes'{'hlr-Number' = ?PATCH_HLR_NUMBER};

	% HLR responds to VLR's MAP_RESTORE_REQ (i.e. it has lost information)
	patch(#'RestoreDataRes'{} = P) ->
	P#'RestoreDataRes'{'hlr-Number' = ?PATCH_HLR_NUMBER};

	% HLR sends subscriber data to VLR/SGSN, including CAMEL info
	patch(#'InsertSubscriberDataArg'{'vlrCamelSubscriptionInfo'=VlrCamel,
	'sgsn-CAMEL-SubscriptionInfo'=SgsnCamel} = Arg) ->
	Arg#'InsertSubscriberDataArg'{'vlrCamelSubscriptionInfo'=patch(VlrCamel),
	'sgsn-CAMEL-SubscriptionInfo'=patch(SgsnCamel)};

	% HLR sends subscriber data to gsmSCF
	patch(#'AnyTimeSubscriptionInterrogationRes'{'camel-SubscriptionInfo'=Csi} = P) ->
	P#'AnyTimeSubscriptionInterrogationRes'{'camel-SubscriptionInfo'=patch(Csi)};

	patch(asn1_NOVALUE) ->
	asn1_NOVALUE;

	% CAMEL related parsing

	% this is part of the SRI Response (HLR->GMSC)
	patch(#'GmscCamelSubscriptionInfo'{'o-CSI'=Ocsi, 't-CSI'=Tcsi,
	'd-csi'=Dcsi} = P) ->
	P#'GmscCamelSubscriptionInfo'{'o-CSI'=patch(Ocsi),
	't-CSI'=patch(Tcsi),
	'd-csi'=patch(Dcsi)};

	% this is part of the InsertSubscriberData HLR -> VLR
	patch(#'VlrCamelSubscriptionInfo'{'o-CSI'=Ocsi, 'mo-sms-CSI'=MoSmsCsi,
	'mt-sms-CSI'=MtSmsCsi, 'ss-CSI'=SsCsi} = P) ->
	P#'VlrCamelSubscriptionInfo'{'o-CSI'=patch(Ocsi),
	'mo-sms-CSI'=patch(MoSmsCsi),
	'mt-sms-CSI'=patch(MtSmsCsi),
	'ss-CSI'=patch(SsCsi)};

	% this is part of the InsertSubscriberData HLR -> SGSN
	patch(#'SGSN-CAMEL-SubscriptionInfo'{'gprs-CSI'=GprsCsi,
	'mo-sms-CSI'=MoSmsCsi,
	'mt-sms-CSI'=MtSmsCsi} = P) ->
	P#'SGSN-CAMEL-SubscriptionInfo'{'gprs-CSI'=patch(GprsCsi),
	'mo-sms-CSI'=patch(MoSmsCsi),
	'mt-sms-CSI'=patch(MtSmsCsi)};

	% this is part of the Anytime Subscription Interrogation Result HLR->gsmSCF
	patch(#'CAMEL-SubscriptionInfo'{'o-CSI'=Ocsi,
	'd-CSI'=Dcsi,
	't-CSI'=Tcsi,
	'vt-CSI'=Vtcsi,
	%'tif-CSI'=Tifcsi,
	'gprs-CSI'=GprsCsi,
	'mo-sms-CSI'=MoSmsCsi,
	'ss-CSI'=SsCsi,
	'm-CSI'=Mcsi,
	'mt-sms-CSI'=MtSmsCsi,
	'mg-csi'=MgCsi,
	'o-IM-CSI'=OimCsi,
	'd-IM-CSI'=DimCsi,
	'vt-IM-CSI'=VtImCsi} = P) ->
	P#'CAMEL-SubscriptionInfo'{'o-CSI'=patch(Ocsi),
	'd-CSI'=patch(Dcsi),
	't-CSI'=patch(Tcsi),
	'vt-CSI'=patch(Vtcsi),
	'gprs-CSI'=patch(GprsCsi),
	'mo-sms-CSI'=patch(MoSmsCsi),
	'ss-CSI'=patch(SsCsi),
	'm-CSI'=patch(Mcsi),
	'mt-sms-CSI'=patch(MtSmsCsi),
	'mg-csi'=patch(MgCsi),
	'o-IM-CSI'=patch(OimCsi),
	'd-IM-CSI'=patch(DimCsi),
	'vt-IM-CSI'=patch(VtImCsi)};

	patch(#'T-CSI'{'t-BcsmCamelTDPDataList'=TdpList} = P) ->
	P#'T-CSI'{'t-BcsmCamelTDPDataList'=patch_tBcsmCamelTDPDataList(TdpList)};
	patch(#'M-CSI'{'gsmSCF-Address'=GsmScfAddr} = P) ->
	P#'M-CSI'{'gsmSCF-Address'=?PATCH_GSMSCF_ADDRESS};
	patch(#'MG-CSI'{'gsmSCF-Address'=GsmScfAddr} = P) ->
	P#'MG-CSI'{'gsmSCF-Address'=?PATCH_GSMSCF_ADDRESS};
	patch(#'O-CSI'{'o-BcsmCamelTDPDataList'=TdpList} = P) ->
	P#'O-CSI'{'o-BcsmCamelTDPDataList'=patch_oBcsmCamelTDPDataList(TdpList)};
	patch(#'D-CSI'{'dp-AnalysedInfoCriteriaList'=List} = P) ->
	P#'D-CSI'{'dp-AnalysedInfoCriteriaList'=patch_AnInfoCritList(List)};
	patch(#'SMS-CSI'{'sms-CAMEL-TDP-DataList'=TdpList} = P) ->
	P#'SMS-CSI'{'sms-CAMEL-TDP-DataList'=patch_SmsCamelTDPDataList(TdpList)};
	patch(#'SS-CSI'{'ss-CamelData'=Sscd} = P) ->
	P#'SS-CSI'{'ss-CamelData'=patch(Sscd)};
	patch(#'GPRS-CSI'{'gprs-CamelTDPDataList'=TdpList} = P) ->
	P#'GPRS-CSI'{'gprs-CamelTDPDataList'=patch_GprsCamelTDPDataList(TdpList)};
	patch(#'SS-CamelData'{'gsmSCF-Address'=GsmScfAddr} = P) ->
	P#'SS-CamelData'{'gsmSCF-Address'=?PATCH_GSMSCF_ADDRESS};
	patch(#'O-BcsmCamelTDPData'{'gsmSCF-Address'=GsmScfAddr} = P) ->
	P#'O-BcsmCamelTDPData'{'gsmSCF-Address'=?PATCH_GSMSCF_ADDRESS};
	patch(#'SMS-CAMEL-TDP-Data'{'gsmSCF-Address'=GsmScfAddr} = P) ->
	P#'SMS-CAMEL-TDP-Data'{'gsmSCF-Address'=?PATCH_GSMSCF_ADDRESS};
	patch(#'GPRS-CamelTDPData'{'gsmSCF-Address'=GsmScfAddr} = P) ->
	P#'GPRS-CamelTDPData'{'gsmSCF-Address'=?PATCH_GSMSCF_ADDRESS};
	patch(#'DP-AnalysedInfoCriterium'{'gsmSCF-Address'=GsmScfAddr} = P) ->
	P#'DP-AnalysedInfoCriterium'{'gsmSCF-Address'=?PATCH_GSMSCF_ADDRESS};
	patch(Default) ->
	Default.

	patch_oBcsmCamelTDPDataList(List) ->
	% we reverse the origianl list, as the tail recursive _acc function
	% will invert the order of components again
	patch_oBcsmCamelTDPDataList_acc(lists:reverse(List), []).
	patch_oBcsmCamelTDPDataList_acc([], NewList) -> NewList;
	patch_oBcsmCamelTDPDataList_acc([TdpData\|Tail], NewList) ->
	NewTdpData = patch(TdpData#'O-BcsmCamelTDPData'{}),
	patch_oBcsmCamelTDPDataList_acc(Tail, [NewTdpData\|NewList]).

	patch_tBcsmCamelTDPDataList(List) ->
	% we reverse the origianl list, as the tail recursive _acc function
	% will invert the order of components again
	patch_tBcsmCamelTDPDataList_acc(lists:reverse(List), []).
	patch_tBcsmCamelTDPDataList_acc([], NewList) -> NewList;
	patch_tBcsmCamelTDPDataList_acc([TdpData\|Tail], NewList) ->
	NewTdpData = patch(TdpData#'T-BcsmCamelTDPData'{}),
	patch_tBcsmCamelTDPDataList_acc(Tail, [NewTdpData\|NewList]).

	patch_AnInfoCritList(List) ->
	% we reverse the origianl list, as the tail recursive _acc function
	% will invert the order of components again
	patch_AnInfoCritList_acc(lists:reverse(List), []).
	patch_AnInfoCritList_acc([], NewList) -> NewList;
	patch_AnInfoCritList_acc([Crit\|Tail], NewList) ->
	NewCrit = patch(Crit#'DP-AnalysedInfoCriterium'{}),
	patch_AnInfoCritList_acc(Tail, [NewCrit\|NewList]).

	patch_GprsCamelTDPDataList(List) ->
	% we reverse the origianl list, as the tail recursive _acc function
	% will invert the order of components again
	patch_GprsCamelTDPDataList_acc(lists:reverse(List), []).
	patch_GprsCamelTDPDataList_acc([], NewList) -> NewList;
	patch_GprsCamelTDPDataList_acc([TdpData\|Tail], NewList) ->
	NewTdpData = patch(TdpData#'GPRS-CamelTDPData'{}),
	patch_GprsCamelTDPDataList_acc(Tail, [NewTdpData\|NewList]).

	patch_SmsCamelTDPDataList(List) ->
	% we reverse the origianl list, as the tail recursive _acc function
	% will invert the order of components again
	patch_SmsCamelTDPDataList_acc(lists:reverse(List), []).
	patch_SmsCamelTDPDataList_acc([], NewList) -> NewList;
	patch_SmsCamelTDPDataList_acc([TdpData\|Tail], NewList) ->
	NewTdpData = patch(TdpData#'SMS-CAMEL-TDP-Data'{}),
	patch_GprsCamelTDPDataList_acc(Tail, [NewTdpData\|NewList]).



	% process the Argument of a particular MAP invocation
	process_component_arg(_From, OpCode, Arg) ->
	case Arg of
	asn1_NOVALUE -> Arg;
	_ -> patch(Arg)
	end.

	% recurse over all components
	handle_tcap_components(_From, asn1_NOVALUE) ->
	asn1_NOVALUE;
	handle_tcap_components(From, List) ->
	% we reverse the origianl list, as the tail recursive _acc function
	% will invert the order of components again
	handle_tcap_components_acc(From, lists:reverse(List), []).
	handle_tcap_components_acc(_From, [], NewComponents) -> NewComponents;
	handle_tcap_components_acc(From, [Component\|Tail], NewComponents) ->
	case Component of
	{basicROS, {Primitive, Body}} ->
	io:format("handle component ~p primitive ~n", [Component]),
	case Body of
	% BEGIN
	#'MapSpecificPDUs_begin_components_SEQOF_basicROS_invoke'{opcode={local, OpCode},
	argument=Arg} ->
	NewArg = process_component_arg(From, OpCode, Arg),
	NewBody = Body#'MapSpecificPDUs_begin_components_SEQOF_basicROS_invoke'{argument=NewArg};
	#'MapSpecificPDUs_begin_components_SEQOF_basicROS_returnResult'{result=#'MapSpecificPDUs_begin_components_SEQOF_basicROS_returnResult_result'{opcode={local, OpCode}, result=Arg} = R} ->
	NewArg = process_component_arg(From, OpCode, Arg),
	NewBody = Body#'MapSpecificPDUs_begin_components_SEQOF_basicROS_returnResult'{result=R#'MapSpecificPDUs_begin_components_SEQOF_basicROS_returnResult_result'{result=NewArg}};
	#'MapSpecificPDUs_begin_components_SEQOF_returnResultNotLast'{result=#'MapSpecificPDUs_begin_components_SEQOF_returnResultNotLast_result'{opcode={local, OpCode}, result=Arg} = R} ->
	NewArg = process_component_arg(From, OpCode, Arg),
	NewBody = Body#'MapSpecificPDUs_begin_components_SEQOF_returnResultNotLast'{result=R#'MapSpecificPDUs_begin_components_SEQOF_returnResultNotLast_result'{result=NewArg}};
	% END
	#'MapSpecificPDUs_end_components_SEQOF_basicROS_invoke'{opcode={local, OpCode},
	argument=Arg} ->
	NewArg = process_component_arg(From, OpCode, Arg),
	NewBody = Body#'MapSpecificPDUs_end_components_SEQOF_basicROS_invoke'{argument=NewArg};
	#'MapSpecificPDUs_end_components_SEQOF_basicROS_returnResult'{result=#'MapSpecificPDUs_end_components_SEQOF_basicROS_returnResult_result'{opcode={local, OpCode}, result=Arg} = R} ->
	NewArg = process_component_arg(From, OpCode, Arg),
	NewBody = Body#'MapSpecificPDUs_end_components_SEQOF_basicROS_returnResult'{result=R#'MapSpecificPDUs_end_components_SEQOF_basicROS_returnResult_result'{result=NewArg}};
	#'MapSpecificPDUs_end_components_SEQOF_returnResultNotLast'{result=#'MapSpecificPDUs_end_components_SEQOF_returnResultNotLast_result'{opcode={local, OpCode}, result=Arg} = R} ->
	NewArg = process_component_arg(From, OpCode, Arg),
	NewBody = Body#'MapSpecificPDUs_end_components_SEQOF_returnResultNotLast'{result=R#'MapSpecificPDUs_end_components_SEQOF_returnResultNotLast_result'{result=NewArg}};
	% CONTINUE
	#'MapSpecificPDUs_continue_components_SEQOF_basicROS_invoke'{opcode={local, OpCode},
	argument=Arg} ->
	NewArg = process_component_arg(From, OpCode, Arg),
	NewBody = Body#'MapSpecificPDUs_continue_components_SEQOF_basicROS_invoke'{argument=NewArg};
	#'MapSpecificPDUs_continue_components_SEQOF_basicROS_returnResult'{result=#'MapSpecificPDUs_continue_components_SEQOF_basicROS_returnResult_result'{opcode={local, OpCode}, result=Arg} = R} ->
	NewArg = process_component_arg(From, OpCode, Arg),
	NewBody = Body#'MapSpecificPDUs_end_components_SEQOF_basicROS_returnResult'{result=R#'MapSpecificPDUs_end_components_SEQOF_basicROS_returnResult_result'{result=NewArg}};
	#'MapSpecificPDUs_continue_components_SEQOF_returnResultNotLast'{result=#'MapSpecificPDUs_continue_components_SEQOF_returnResultNotLast_result'{opcode={local, OpCode}, result=Arg} = R} ->
	NewArg = process_component_arg(From, OpCode, Arg),
	NewBody = Body#'MapSpecificPDUs_continue_components_SEQOF_returnResultNotLast'{result=R#'MapSpecificPDUs_continue_components_SEQOF_returnResultNotLast_result'{result=NewArg}};
	_ ->
	NewBody = Body
	end,
	%NewBody = setelement(5, Body, NewArg)
	NewComponent = {basicROS, {Primitive, NewBody}};
	_ ->
	NewComponent = Component
	end,
	io:format("=> modified component ~p~n", [NewComponent]),
	handle_tcap_components_acc(From, Tail, [NewComponent\|NewComponents]).


	% Erlang asn1rt has this strange property that all incoming EXTERNAL types are
	% converted from the 1990 version into the 1994 version. The latter does not
	% preserve the encoding (octet string, single ASN1 type, ...). During encoding,
	% it then uses the OCTTET-STRING encoding, which is different from the MAP
	% customary single-ASN1-type format.
	asn1_EXTERNAL1994_fixup({'EXTERNAL', DirRef, IndRef, Data}) when is_list(Data);is_binary(Data) ->
	% our trick is as follows: we simply convert back to 1990 format, and explicitly
	% set the single-ASN1-type encoding. asn1rt:s 'enc_EXTERNAL'() will detect this
	#'EXTERNAL'{'direct-reference' = DirRef, 'indirect-reference' = IndRef,
	'encoding' = {'single-ASN1-type', Data}};
	asn1_EXTERNAL1994_fixup(Foo) ->
	Foo.


	handle_tcap_dialogue(_From, Foo = {'EXTERNAL', DirRef, IndRef, Data}) ->
	asn1_EXTERNAL1994_fixup(Foo);
	handle_tcap_dialogue(_From, Foo) ->
	Foo.


	%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
	% Actual mangling of the decoded MAP messages
	%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
	mangle_map(From, {Type, TcapMsgDec}) ->
	case {Type, TcapMsgDec} of
	{'unidirectional', #'MapSpecificPDUs_unidirectional'{dialoguePortion=Dialg,
	components=Components}} ->
	NewDialg = handle_tcap_dialogue(From, Dialg),
	NewComponents = handle_tcap_components(From, Components),
	NewTcapMsgDec = TcapMsgDec#'MapSpecificPDUs_unidirectional'{dialoguePortion=NewDialg, components=NewComponents};
	{'begin', #'MapSpecificPDUs_begin'{dialoguePortion=Dialg, components=Components}} ->
	NewDialg = handle_tcap_dialogue(From, Dialg),
	NewComponents = handle_tcap_components(From, Components),
	NewTcapMsgDec = TcapMsgDec#'MapSpecificPDUs_begin'{dialoguePortion=NewDialg, components=NewComponents};
	{'continue', #'MapSpecificPDUs_continue'{dialoguePortion=Dialg, components=Components}} ->
	NewDialg = handle_tcap_dialogue(From, Dialg),
	NewComponents = handle_tcap_components(From, Components),
	NewTcapMsgDec = TcapMsgDec#'MapSpecificPDUs_continue'{dialoguePortion=NewDialg, components=NewComponents};
	{'end', #'MapSpecificPDUs_end'{dialoguePortion=Dialg, components=Components}} ->
	NewDialg = handle_tcap_dialogue(From, Dialg),
	NewComponents = handle_tcap_components(From, Components),
	NewTcapMsgDec = TcapMsgDec#'MapSpecificPDUs_end'{dialoguePortion=NewDialg, components=NewComponents};
	%{_, #'Abort'{reason=Reason} ->
	_ ->
	NewTcapMsgDec = TcapMsgDec
	end,
	io:format("new TcapMsgDec (Type=~p) ~p~n", [Type, NewTcapMsgDec]),
	{Type, NewTcapMsgDec}.